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arXiv · 1705.06827

Spintronic signatures of Klein tunneling in topological insulators

Yunkun Xie·Yaohua Tan·Avik W. Ghosh
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Abstract

Klein tunneling, the perfect transmission of normally incident Dirac electrons across a potential barrier, has been widely studied in graphene and explored to design switches, albeit indirectly. We show that Klein tunneling maybe easier to detect for spin-momentum locked electrons crossing a PN junction along a three-dimensional topological insulator surface. In these topological insulator PN junctions (TIPNJs), the spin texture and momentum distribution of transmitted electrons can be measured electrically using a ferromagnetic probe for varying gate voltages and angles of current injection. Based on transport models across a TIPNJ, we show that the asymmetry in the potentiometric signal between PP and PN junctions and its overall angular dependence serve as a direct signature of Klein tunneling.

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Yunkun Xie, Yaohua Tan, Avik W. Ghosh. 2017-05-18. Spintronic signatures of Klein tunneling in topological insulators. https://doi.org/10.1103/physrevb.96.205151

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